Hollow handle knife



ilnited States HQLLOW HANDLE KNIFE Felix A. Mirando, Providence, andWaldemar .l'. Elsdorfer, Cranston, Rl, assignors to Imperial KnifeCompany, Inc., Providence, Rl, a corporation of Rhode Island Filed Nov.13, 1957, Ser. No. 696,114

8 Qlairns. (Cl. 30165) This invention relates to a hollow handle knife.Principally, our invention pertains, and will be so described, to ahollow handle table knife. However, the invention is not to be solimited except to the extent indicated in the appended claims, and ingeneral the invention is concerned, therefore, with knives wherein thehandle is rigidly connected to the blade and is hollow.

For many years there have been only two kinds of table knives. One isthe so called one-piece knife. It consists of a blade and a handle whichare made from a single piece of metal, e.g., stainless steel. The metalis forged to the desired shape and the blade then is sharpened. Thehandle of such a knife is obviously solid, i.e., metal through andthrough. This type of knife has certain highly desirablecharacteristics. For instance, the connection between the knife andhandle is very strong so that there is no tendency for the blade tobreak off. Nor can dirt enter between any joint that connects the handleto the blade, so that the knife always is" easily cleaned. Moreover, theknife is attractive in appearance because smooth flowing lines can beprovided between the bolster and the handle.

However, a one-piece knife has several drawbacks, chief among which arefabrication expense and heavy weight. The fabrication expense arisesfrom the fact that the metal of the knife must be forged at high heatand under substantial pressure, requiring expensive heavy dutyequipment. The heavy weight of the knife is inherent and arises from thesolidity of the handle. This same factor, i.e., weight, increases thecost of the knife. In addition, the nature of the fabrication makes itdiflicult to secure many desirable designs inasmuch as the heavyembossings and delicate traceries which are characteristic of many knifehandle patterns cannot economically be imparted by heavy duty forgingdies.

The other type of commercial knife is the so called hollow-handle knife;This knife consists of three parts, to wit, a blade and two halves of ahandle. It has been the practice to secure the two halves of the handleto one another and to provide the blade with a tang which extendedthrough an opening at the front of the handle where the two halves werejoined, a suitable connection of some sort being included to attach thetang to the handle. The advantages of this type of knife was that it waslight in weight, comparatively inexpensive to make, and capable of beingprovided with various ornate designs at a relatively low cost inasmuchas the halves of the handle were made of sheet metal and could be shapedas desired with the aid of comparatively light dies and presses.

However, heretofore the hollow-handle knife had serious drawbacks. Forinstance, 'the blade tended to become disengaged from the handle ifsubjected to rough handling. Also, food particles and dirt tended toaccumulate in the joint between the handle and blade. Furthermore, dueto the inherent construction of the knife, it was extremely difiicultand usually impossible to provide a pleasing fillet between the bolsterand the yet which has the blade integral, i.e., in one piece, with thehandle.

It is another object of our invention to provide a knife or" thecharacter described in which any desired pleasing line can be utilizedat the joint between the bolster and blade despite the fact that thehandle is hollow.

It is another object of our invention to provide a knife of thecharacter described which is extremely sturdy, can be made at arelatively low cost, and cannot be distinguished, except for its weightand hollow sound, from a one-piece knife.

It is another object of our invention to provide a knife of thecharacter described which, although having a hollow handle, has no jointbetween the handle and blade that can be weakened with usage or whichcan provide a pocket for the accumulation of dirt.

Other objects of our invention in part will be obvious and in part willbe pointed out hereinafter.

Our invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts, which will beexemplified in the knives hereinafter described and of which the scopeof application will be indicated in the appended claims.

In the accompanying drawings, in which are shown various possibleembodiments of our invention,

Fig. 1 is a perspective view of a finished knife constructed pursuant toour invention;

Figs. 2 and 3 are enlarged sectional views taken substantially along thelines 2-2 and 33, respectively, of Fig. 1;

Fig. 4 is a top view of said knife;

Fig. 5 is an exploded view of the two parts which constitute the knife;

Fig. 6 is an enlarged sectional view through the blade of the knifeduring the assembly of the two parts of said knife;

Fig. 7 is a sectional view through the handle of the knife andindicating a different method of securing the two parts of the knife toone another;

Fig. 8 is a view similar to Fig. 7 but showing another method ofassembling the two halves of the knife; and

Fig. 9 is a view similar to Fig. 3, but to a slightly larger scale andillustrating a modified form of our invention.

In general, we carry out the several objects of our invention byfabricating a knife from two halves which desirably, but notnecessarily, are mirror images of one another. More particularly, weform the knife from two halves which are joined longitudinally to oneanother over the entire length of the knife, the joint extending alongthe top edge of the handle and blade, down the tip of the blade, alongthe bottom edge of the handle and blade, and up the back of the handleas one continuous seam. It thus will be apparent that the knife isfashioned from two halves, each of which includes one side half of ahandle and one side half of a blade, the two halves complementallymatching one another so that together, when assembled, they define acomplete knife. In each half of the knife, the handle portion is unitary(in one piece) with the blade portion, so that when the two halves arejoined they form an integral knife that consists of but a single piece,whereby the blade is firmly and rigidly secured to the handle and thereis no seam between the two, i.e., the handle and blade, for dirt toenter into and lodge. Each of the halves of the knife thus joined will,as is obvious, constitute one side of a handle and one side of a blade.Thereby, the finished blade and also the finished handle consists of twoside parts joined at the top and bottom edges as well as at the exposedend edges.

Thus, a transverse section through the knife, for instance, would showthese two side halves. However, in the finished knife the seam has beenground down and finished off so that it is not visible and the knifeseems to be made of a single piece of forged metal.

Preferably, the two halves are made from sheet metal and thereby readilycan be formed to the desired contours and configurations so as toinclude desired design features.

The two halves of the knife are joined to one another permanently andrigidly by any suitable method and means well known to the art and whichis such that there is nothing but solid metal at the joint. The metaleither can be added material or the very material of the two knifehalves themselves. Thus, for instance, the two parts can be joined toone another by welding, brazing or soldering, wherein a fusible metalrod is used which deposits metal along the seam to unite the two halves.Alternatively, the two halves can be joined by autogeneus welding. Thewelding can be done with the use of a gas flame, or an electric are, orby the heat generated simply by the passage of electric current. Thewelding also may be done under pressure and heat, as by introducing thehalves, clamped together, into a furnace, or the welding may be done byintroducing a fusible welding or soldering material into the hollowbetween the halves, clamping them. and introducing them into a furnace,whereupon the fusible material will liquify and run into and fill theseam between the two halves. The two halves even can be joined bycementing or by cold welding, i.e., by mechanical or hydraulic swaging,under great pressure.

It will be obvious that in the practice of our invention the two halvesof the handle are internally concave. The blade halves, however, neednot be internally concave, but if not, desirably are plane. In thepreferred form of our invention the internal surfaces of the bladeportions of the two knife halves are at least slightly concave beforetheir permanent joinder to one another. Subsequent to the joinder, theseam is dressed down so that it no longer will be visible, and an edgeof the blade is sharpened, this sharpening optionally and usually takingplace through the seam itself, so that the seam actually may form partof or all of the cutting edge.

However, it will be observed hereinafter that it is within the scope ofourinvention to offset the seam so that the cutting edge will be throughthe original material of one of the halves of the knife, thisarrangement being desirable under certain circumstances where closecontrol is to be exercised over the composition of the metal in thecutting edge, since under some ambient conditions the joining of the twohalves to one another by means of added metal may leave a sharpened edgewhich does not have a very high hardness. It should be understood,however, that we do not disclaim a knife wherein the added metal-formspart or all of the cutting edge inasmuch as we are able to utilize, bystandard methods, added metal of great hardness, e.g., a steel weldingrod having a very substantial carbon content, the welding conditionsbeing so controlled that the deposited metal of the weld contains a highcarbon content and therefore is able to maintain a sharp cutting edgeReferring now in detail to the drawings and, more particularly, to Figs.15, the reference numeral it) denotes a knife constructed in accordancewith our invention and made from two side halves 12, 14, which are shownseparated from one another in Fig. 5. Each of said halves includes aside handle portion 16 and a side blade portion 18. Each side handleportion is elongated and is internally concave, as can be seen from theshading in Fig. 5 and the cross-section in Fig. 2. Each side bladeportion is slightly concave, as best can be seen in Fig. 3; that is tosay, it is somewhat dished transversely. There also is a slight dishingat the tip of the blade portion.

The side handle portion 16 and side blade portion '18 of each of theside halves are made of a single piece of sheet metal integrally joinedat a side bolster portion 20. Each of said halves is shaped to itsdesired configuration, as by a simple stamping and forming operation ina standard press, the shape illustrated being a plain one which iseasily imparted to sheet metal by non-complex dies. In the form of ourinvention being described, the two knife halves 12, 14 are of identicalshape but are mirror images of one another, that is to say, there is oneleft half and one right half which are of identical contour so that theycan be butted against one another in exact registration.

The two knife halves are brought into registration and are joined to oneanother in any suitable manner, as has been mentioned above, so as toform a continuous seam 22 which extends all around the peripheral edgeof the knife, i.e., both along the handle and the blade. A part of thisscam is at that portion of the blade which ultimately will become thecutting edge. The knife then is put through the usual series offinishing operations which are standard for any one-piece forged knife.The knife is dressed to remove external evidence of the seam and ispolished and has an edge of the blade sharpened, e.-g., by grinding andhoning. Optionally the blade also may be hollow ground, in which eventcare must be exercised to select a suitably thick sheet metal, or toshape the blade portions of the knife halves prior to joining saidhalves so as to provide a concave longitudinally extending curvaturewhich is characteristic of a hollow ground blade whereby it will not benecessary to remove too much metal during the actual hollow grindingoperation.

It will be observed by reference to Fig. 3 that the sharp edge 24 of theknife blade includes the material of the seam 22, this material beingsufficiently tough and hard to maintain an edge for the length of timedesired for the particular knife being made. As has been noted above, byjudicious selection of the material used for welding, a seam as hard asis desired can be obtained. For instance, if a particularly hard edge isdesired, the weld can be eifected with a high carbon fusible weldingrod, the deposit of which is under conditions, e.g., with proper fluxesor under an inert gaseous blanket, such that a high carbon content ismaintained in the weld metal deposited. Optionally also, the weld can beeffected'autogenously and the metal of the two halves can be selectedfrom a steel of such a carbon content or such an alloy that it is ableto maintain its edge so that at the seam 22 the metal will not quicklypermit dulling of the edge.

In Fig. 6 we have shown one way of forming the seam. As thereillustrated, the two halves, after being brought into exact registry,are firmly pressed against one another as by the jaws 26 of a clamp.Then a welding, brazing or soldering rod 28 and flame 30 of a torch aremoved along the joint between the two knife halves to join the two in amanner well known in the art.

An alternative method of joining the two knife halves is illustrated inFig. 7. In this method the two side halves 12, 14, arranged inregistration, are inserted between the matching edges 32, 34 of anelectric resistance welder. By relieving the jaws, as at 36, currentflow is concentrated at the junction between the two halves so that theedges of the two halves will be heated to incandescence and, under thepressure exerted between the two jaws, will be autogenously welded toone another by resistance welding. This weld, of course, like theprevious welds discussed, forms a continuous'seam over the full lengthof the knife at both its top and bottom edges as well as its two endedges.

Still another method of securing the two side halves of the knife to oneanother permanently and rigidly is illustrated in Fig. 8. In this methodthe two jaws 38, 40 of a clamp, which are shaped to match the two halvesof the knife over the full lengths thereof, are applied to the saidhalves after registry of the edges. The jaws are pressed toward oneanother, as by screw means that normally form part of a clamp, and areinserted in a gas oven. Metallic material 42, e.g., hard solder, isinserted between the two halves before clamping, this material beingfusible at a temperature lower than the deformation temperature of thematerial of which the two halves of the knife are formed. The gas ovenis maintained at a temperature sufficiently high to melt the fusiblematerial 42 but not high enough to permit deformation of the halves ofthe knives. The molten material will flow into the seam between the twohalves where it will be held by capillary attraction. We have found thatit is not necessary to hold the two knife halves in any particularposition in the oven or to move them therein in order to insuredistribution of the molten material throughout the entire seam inasmuchas the said material completely fills the entire length of the seam bycapillary action. Thereafter when the two halves are taken out of theoven, the fused material solidifies and permanently and rigidly holdsthe two halves of the knife to one another.

It should be mentioned that where additional material is employed, forexample, in connection with the methods described in Figs. 6 and 8, suchmaterial does not necessarily have to be ferrous inasmuch as non-ferrous(brazing and soldering) materials also have been found to functionsatisfactorily. The difierence in color can be con cealed by plating,and since the seam can be maintained as a hairline, it will not benoticeable where it crosses the sharp edge. Moreover, by judiciousselection of nonferrous alloys, a silvery color can be secured whichmatches the material of which the knife halves are formed, this usually,although not necessarily, being stainless steel. Furthermore, it iswithin the scope of our invention to form the knife halves of alloymaterials of other than a silvery color which may match, for example,the color of a brazing material utilized to secure the halves to oneanother.

It has been noted above that although in one of the forms of ourinvention, and particularly that described in detail with reference toFigs. 1-5, the two halves of the knife are mirror images of one another,we also contemplate manufacturing a knife in which the portion of theseam that runs adjacent to the cutting edge of the blade is notcoincident therewith. Such a knife, denoted by the reference numeral 44,is illustrated in Fig. 9. Said knife consists of two halves 46, 48. Thehandle portions of these halves preferably are mirror images of oneanother. For example, they may be identical with the handle portions 16hereinabove described. Likewise the bolster portions 20 may beidentical. However, the blade portions of the two halves are unlike. Theblade portion of the half 48 includes the entire cutting edge andterminates at a sloping shoulder 50 above said edge. The blade portionof the half 46 terminates at a complementary shaped sloping surface 52.The two halves of the knife are joined in any suitable manner such ashas been described above.

Attention is called to the smooth line connecting the bolster of theknife to the blade, this configuration heretofore having only beenobtainable in a one-piece forged knife. It will be observed that byvirtue of the unitary construction of the blade and handle portions ofeach of the knife halves and the secure connection of the two halves to-.one" another, the knife is extremely strong and the blade cannot, bebroken away from the handle by rough usage. Moreover, there is no jointbetween the bolster and blade in which dirt can lodge, the seam thatjoins the two halves constituting solid metal which is unitarywith saidhalves and therefore can be dressed down whereby an absolutely smoothunbroken surface joins said two halves along the seam.

It thus will be seen that we have provided knives which achieve thevarious objects of our invention and are well adapted to meet theconditions of practical use.

As various possible embodiments might be made of our invention and asvarious changes may be made in the embodiments above set forth, it is tobe understood that all matter herein described or shown in theaccompanying drawings is to be interpreted as illustrative and not in alimiting sense.

Having thus described our invention, we claim as new and desire tosecure by Letters Patent:

1. A hollowhandle knife comprising two registered halves, each said halfincluding an internally concave handle portion and an internally concaveblade portion, each said handle portion forming one side half of theknife handle and each said blade portion forming one side half of theknife blade, the blade portion and handle portion of each halfconsisting of a single piece of metal, and means unitarily joining thetwo halves to one another around the entire periphery of the knife in asingle seam which extends along the entire top and bottom of the knifeand along the tip of the blade and free end of the handle.

2. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and means unitarily joining the two halves to oneanother around the entire periphery of the knife in a single seam whichextends along the entire top and bottom of the knife and along the tipof the blade and free end of the handle, said means providing anexternally smooth unbroken surface between the two halves.

3. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and means unitarily joining the two halves to oneanother around the entire periphery of the knife in a single seam whichextends along the entire top and bottom of the knife and along the tipof the blade and free end of the handle, one of the edges of the bladeformed by the two blade portions being sharpened along a portion of theseam.

4. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and

means unitarily joining the two halves to one another with solid metalaround the entire periphery of the knife in a single seam which extendsalong the entire top and bottom of the knife and along the tip of theblade and free end of the handle.

5. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and a weld joint unitarily joining the two halves to oneanother around the entire periphery of the knife in a single seam whichextends along the entire top and bottom of the knife and along the tipof the blade and free end of the handle. a

6. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one .side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and a brazed joint unitarily joining the two halves toone another around the entire periphery of the knife in a single seamwhich extends along the entire top and bottom of the knife and along thetip of the blade and free end of the handle.

7. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and a solder joint unitarily joining the two halves toone another around the entire periphery of the knife in a single seamwhich extends along the entire top andbottom of the knife and along thetip of the blade and free end of the handle.

8. A hollow handle knife comprising two registered halves, each saidhalf including an internally concave handle portion and a blade portion,each said handle portion forming one side half of the knife handle andeach said blade portion forming one side half of the knife blade, theblade portion and handle portion of each half consisting of a singlepiece of metal, and an autogenous joint unitarily joining the two halvesto one another around the entire periphery of the knife in a single seamwhich extends along the entire top and bottom of the knife and along thetip of the blade and free end of the handle.

References Cited in the file of this-patent UNITED STATES PATENTS Re.8,873 Fallows Aug. 26,1879 70,352 Nichols Oct. 29, 1867 338,521 HartMar. 23, 1886 388,970 Hart Sept. 4, 1888 526,033 Griswold Sept. 18, 1894689,049 Hirsch Dec, 17, 1901 1,541,307 Zinn June 9, 1925 2,285,013 BurnsJune 2, 1942 2,440,136 Barnes Apr. 20, 1948 FOREIGN PATENTS 6,060 GreatBritain Sept. 12, 1907

